Pull-out switch block



SePt- 221936- J. w. Dow'LER- 2,055,006

PULL-OUT SWITCH BLOCK Filed March 27, 1935 I 2 Sheets-Sheet l E005 Wwzef ATTORNEY.

Sept. 22, 1936. J, W DQWLER n I 2,955,006

PULL-OUT SWITCH BLOCK l l Y Filed March 27, 1935 2 Sheets-Sheet 2 ATTORNEY.

Patented Sept. 22, 1936 UNITE D` SSTATES PATENT OFFICE PULL-OUT SWITCH BLOCK Application March 27, 1935, Serial No. 13,211

6 Claims.

My inventionis an improved pull-out switch block having a reversible cover or closure for a base and permitting the making or thebreaking of the circuit or circuits through the switch block.

5 while shielding the operative from danger at all times and insuring that the closure is securely held on the base in either the circuit making or the circuitv breaking position.

In the preferred embodiment of' my improvei ments the base contains one or more chambers each having therein a line contact and a load contact which are each housed between an insulating wall and a shielding contact. The shielding contacts are dead when the cover is removed, and are preferably electrically connected with springA fuse clips forthe engagement of a fuse or fuses carried by the closure. The closure is `also provided with contacts which, in one position of the closure, establish conducting relation between the respective line'and load contacts and their respective shielding contacts, and through the fuse clips and fuses establish conductance between the line contact and the load contact. In the reverse position of the closure, the contacts carried thereby are free from engagement with the line contacts or load contacts, but in both positions the spring clips firmly grip the fuse so as to hold the cover securely in place upon the base. Y

50 The characteristic features and advantages of my improvements will further appear from the following description and the accompanying drawings in illustration thereof. y

In the drawings, Fig. 1 is a top plan view of the base of my improved pull-out switch block with the cover contacts in place to connect the line terminals and load terminals with their'respective shielding contacts; Fig. 2 is an irregular transverse-sectional view of my improved de'- 40 vice with the cover in'place; Fig. 3 is a detached exploded view showing the relationshipof a line contact, a shielding contactv therefor, the insulation between them, and a fuse clip; Fig. 3a is a top plan view of the assembly vshown in Fig.

3; Fig. 4 is a longitudinal sectional view through the device shown in Fg..2 'with the'fuse omitted for greater clarity; Fig. 5 is a side elevation of a detached closure, with the fuse omitted for greater clarity of illustration; Fig. 6 is a bottom plan view of the closure shown in Fig. 5; and Fig. '7 is a transverse view taken .on the line 'I-I of Fig. 5. I

In the embodiment of my invention illustrated in the drawings, an insulating base member I is provided with the side walls 2 and 2v', the end walls 3, and 3. and with the partition wall sections II` and d forming the chambers 5 and 5'. Tubular line terminals 6 and 6. are provided with conductoreclamping screws 'I'. and 'I' and with conducting flat Shanks 8 and 8 which are inserted through slots 9 and 9 in the end wall 3 and are secured by the screws I0 and I0 to ,v conductingVv plates II, II in the bottoms of the chambers 5 and 5 (Fig. 4).v

The conducting plates II, II have extensions ri I2 and I2 disposed angularly thereto and having up-bent ends I3 and I3 forming contact blades adjacent to oppositesides of the wall 4 an-d partly housed in recesses I4 and I4 in such wall section. Each of the plates II, II contains l5. an aperture for the passage of an insulatingy collar I54 and has superposed thereon an insulating spacer I6 having upturned edgesl and electrically separating the plates II, II' and extensions I2, I2 from the bases I1, I'I' of angu- 20 lar contact members provided with up-bent ends I8, I8 which lie parallel to the contact blades I3, I3"`and' shield'the latter `against being accidentally touched when the chambers 5, 5 are uncovered. Fuse 'clips 20, 2,0 are seated on the 25 members I'I, II'. Boltsv 2I, 2I pass through apertures 22, 22..'in the base I and through the collars I5, spacers I6, contacts I'I, I'I and clips 20, 20', and have threaded thereon the nuts 23, 23' to. hold the .parts in fixed relationship to one 30 another and to the base without any electrical contact between the fuse clips 20, 20 and the line contacts I3, I3', and without any electrical contact between the shielding contacts I8, I8 and the line contacts I3, I3. 35

The niernloers I2 and I2 and the 'members I'I and I'I are so shaped that the line contacts vI3, I3 and the shielding contacts I8, I8".lie close to the inner end of the insulating partition wall 4 and are spaced a considerable distance from 40 the end wall 3.

At the` opposite ends of the block I, tubular load terminals 6a and 6b, provided with clamp.- ing screws Ia and 1b, have Shanks 8a and 8b inserted through slots 9a and 9b in the wall 3. 45 The shanks 8a and 8h are secured by screws I0a and |012v to conducting plates IIa and I Ib in the bottoms of the chambers Brand 5' (Fig. 4)

The conducting plates Ila have angularly disposed extensions I2a and I2b terminating in 50 up-bent ends forming Contact blades [3a and I3b partly housed in recesses Illa and I4b formed in the opposite sides of the insulating partition w'all section 14. The plates IIa and IIb contain apertures for insulating collars I5 and have su- 55 perposed thereon insulating spacers I 6 which support the conducting plates I 'Ia and I'Ib, which are so shaped that their up-bent ends I 8a and I 8b lie parallel with and shield the contact blades I3a and I3b. Spring fuse clips 20a and 2Gb have their bases seated on the insulating spacers I6 and screws 2Ia and 2lb pass through the apertures 22a and 2217, through the collars I5, insulators I6, conductors Ila and I'Ib and fuse clips 20a and 20D into threaded engagement with nuts 23a and 23h to clamp the parts together.

The side wall 2 has the tapering walls 2a projecting inwardly therefrom and the wall 2 has the tapering walls 2b projecting inwardly therefrom to form guideways,l 24, 24' midway the lengths of the walls 2 and 2'.

A cover or closure 25 of insulating material is provided with a drop pull handle 28 and is of such size as to overlap the inner edges ofthe walls 2, 2', 3, 3' when centered over the base member. A pair of insulating diaphragms 2'I are secured to the inner face of the cover 25 transversely of the length thereof and have formed therein curved seats 28 (Fig. 7) for the engagement of cartridge fuses 29 and projecting tongues 30 adapted to be positioned' in the guideways 24 and 24.

A pairV of fingers 3I, 3I' (Fig. 6) of insulating material, depend from the cover 25 adjacent to the diaphragms 21 and contacts 32, 32 are inserted in slots in the fingers 3|, 3I' and riveted to the respective fingers so as to form connected contacts on each side thereof.

A'second pair of ngers 33, 33' of insulating material depend from the cover 25 adjacent to an end thereof, the ngers 33 and 33' being spaced from theV diaphragms 2l. Contacts 34, 3ft are 'inserted in slots in the' fingers 33, 33 and are riveted thereto to form connected contacts on each side of the respective ngers.

The fuse clips and fuses are symmetrically positioned relative to center lines of the structure so that the fuses engage and are held by the clips regardless of whether the cover 25 is applied to the base in the manner illustrated in Fig. 4, or in therevers'e position thereto. The contacts, however, are so positioned in the base member and on the cover member that when'the cover applied to the base in the position shown in Fig. 4, the contact 32 enters between and electrically connects the contacts I3 and I8, the contact 32 enters between and electrically connects the contacts I3' and I3', the contact 34 enters between and electrically connects the contacts I3a and I8a, and the contact 34' enters between and electrically connects the contacts 13b and I8b. Y v

In this position, currentV from the line contact 6 flows through the shank 8, plate II, extension I2, contact I3, contact 32, contact I8, plate I l, clip 20, cartridge 29, clip 20a, plate Ila, Contact 18a, contact 34, Contact I3a, extension I2a, plate IIa, shank 8a, and terminals 6a to the load'conductor. 1 vSimilarly Ycurrent entering from a line conv `ductor.'through the line terminal 6 passes extensionV I2',V blade E3', Contact 32', contact I8', plate I'I',

through the shank 8', plate II',

clip 29', fuse 29, clip 23h, plate I'Ib, contact I8b, contact 34', contact I3b, extension I2b, plate IIb, shank 8b, and load terminals 6b to the load conduct'or.

l When, however, the cover 25 is applied to the Ybase. member inthe reverse or upside down position from that shown, the contacts 3,4 and 34' occupy the vacant spaces indicated by dotted lines (Fig. 1) between the wall 3 and the line contacts I3, I3'. The contacts 32, 32' then occupy the vacant spaces indicated by dotted lines between the inner end of the partition 4 and the load contacts I3a and I3b. Consequently there is no iiow of current, notwithstanding the engagement of the fuses and the spring clips, owingV to the fact that the gapsV between the line contacts I3, I3' and their shielding contacts I8, I 8' and the gaps between the load contacts |301. and I3b and their shieldingV contacts I8a and |817 are now operi.

Having 4described my invention, I claim:

1. A pull-out switch block having a base member and a cover member, one' of said members having connected therewith a fuse clip and a line terminal insulated from said fuse clip and the other of said members having connected there-V with a fuse forA engagement in said clip an@ meansy for connecting said fuse clip with said line ter-f minal. Y

2. A pull-out switch block having a base mem-A ber and a cover member, one of said members having fuse clips connected therewith and the other of said members having a fuse connected therewith forV engagement with said fuse clips, a pair of contacts on one of said members oiset from the respective fuse clips, and a pair of contacts on the other of said members adapted to' engagev said first named pair of contacts in one position of said cover member and to be free from engagement with said contacts in the reverse position of said cover member, said fuses engaging said clips and holding said cover member and base member together in both positions of said cover member.

3. A pull-out switch block having a base member and a cover member, one of sai-d members having a fuse connected therewith and the other of said members having fuse clips for the engagement of said fuse, and contacts on the re`V spective members which engage one another in one position of said cover member relatively to said base member and are disengaged from one another in another position of said cover member relative to said base member, said fuse and clips holding said members together in both the engaging and disengaging positions of said con tacts. c

4. A pull-out switch block comprising a base containnig a chamber, a line contact and a load l on a contact movable into conducting relationv with said load contact and its shielding contact, Y

said closure having connected therewith a fuse S65 movable into conducting relation with said fuse clips.

5. A pull-out switch block comprising a base V Vcontaining a plurality of chambers separated by insulating wall sections having a passage between the ends thereof, a line contact on each side of and shielded by one of said wall sections, a load contact on each side of and shielded by the other of said insulating wall sections, a shielding contact in front of, but electrically insulated from' each of said line contacts and load contacts, a fuse clip connected with each of said shielding contacts, a closure having a diaphragm transversely thereof and movable into said passage, fuses carried by said diaphragm and adapted for engagement with fuse clips aforesaid, and contacts carried by said closure and movable into conducting engagement with the respective line and load contacts and the complementary shielding contacts therefor in one position of said closure, said closure contacts being disengaged from the line and load contacts in the reverse position of said closure.

6. A pull-out switch block comprising a base containing a plurality of chambers separated by insulating Wall sections having a passage between the ends thereof, a line contact on each side of and shielded by one of said Wall sections, a load contact on each side of and shielded by the other of said insulating Wall sections, a shielding contact in front of, but electrically insulated from each of said line contacts and load contacts, a fuse clip connected with each of said shielding contacts, a closure having a diaphragm transversely thereof and movable into said passage, fuses carried by said diaphragm and adapted for engagement With said fuse clips aforesaid, and contacts carried by said closure and movable into conducting engagement with respective line and load contacts and the complementary shielding contacts thereof in one position of said closure, said closure contacts being disengaged from the line and load contacts in the reverse position of said closure, but said diaphragm adapted to lie in said passage in both positions of said closure.

JACOB W. DOWLER. 

